1. FIELD OF THE INVENTION
This invention relates to an apparatus for resurfacing the bearing surfaces of truck, trailer and other motor vehicle axles. Most importantly, it is capable of resurfacing axle bearing surfaces while the axle remains on the vehicle, i.e., the axle need not be removed from the vehicle in order to rapidly and accurately resurface the bearing surfaces.
2. SUMMARY OF PRIOR ART
Motor vehicles and especially trailers utilize roller bearings to provide low friction interfaces between stationary axles and rotating wheels. These roller bearings combine low frictional coefficients with minimum maintenance and an extended service life. The roller bearing assembly itself is pressed into the wheel hub and retained by a rather tight friction fit. To facilitate the mounting of the wheel and bearing on the axle, the inner diameter of the roller bearing assembly is a somewhat loose fit upon the vehicle axle. As the bearing ages, the inner races and roller bearings become pitted, causing increased friction and thus heat generation causing the lubricant to lose its effectiveness. Seizing of the bearing components and their rotation as a single unit is a normal mode of failure. Then the entire wheel and bearing continues to rotate about the shaft and rapidly damage the bearing surface of the axle. In addition to replacing the defective roller bearing assembly, the axle surface which is secured to the truck or trailer bed must be restored or the axle replaced before the vehicle can be returned to service.
The lack of periodic inspection and lubrication often causes bearings to fail in service, sometimes catastrophically, when a truck or trailer rig is in transit in a location remote from a repair facility. Heretofore, if the axle bearing surfces are damaged, the axle must be dismounted from the vehicle, metal built up around the worn journal by welding and then the built-up portion ground down to the proper diameter and axis on a grinding lathe. The axle is then remounted upon the vehicle and the vehicle is returned to service. This procedure, of course, often results in lost time of a day or more, costing the carrier the resultant lost wages and repair expenses and delaying the delivery of the goods, etc.
An analysis of the time required to perform these repairs reveals that the majority of time is spent removing and remounting the axle. Fasteners rendered immovable by rust may have to be cut with an oxyacetylene torch and replaced. Repositioning and holding the heavy axle during remounting further contribute to difficulty and expense of this time consuming procedure. Furthermore, once the axle is removed, it must be transported to a machine shop, perhaps miles away, having grinding equipment of sufficient capacity to accommodate the axle. Likewise, if the decision is made to replace the axle, its procurement may add to the downtime of the vehicle. A portable device capable of repairing bearing surfaces destroyed by seized ball bearings which does not require the removal of the axle from the vehicle provides a substantial advantage to the trucker and the repair facility.